IR sensor

My group is tasked to design a robot to grab an empty drink can.
We are thinking of using IR sensors to be fixed on the hnad of the robot to detect the empty drink can. This is done by fixing the IR emitter on one side of the hand and the receiver on the other side. When the can blocks the IR rays, the hand will be activated to close and grab the can.
the size of the robot arm is not to exceed 8cm by 10cm.
May i ask what type of IR sensor would you recommend? what are the specifications of the sensors?
What’s the maximum distance the emitter and receiver can be placed apart (yet the receiver can still detect) the price? dimensions? weight?

thanks :unamused: